In order to adapt to the development of high-energy laser anti-missile weapon system, with the support of the Advanced Research Projects Agency of the U.S. Department of Defense, Lincoln Laboratory began to implement the development plan of high-precision laser radar code-named "Tang Huo" in the early 1970s, and developed the technologies of long-range missile tracking and laser beam aiming. 1984 "Star Wars Project" was launched in the United States, Lincoln Laboratory received further funding and made progress in a series of experiments.
"Tang Huo" lidar adopts a giant transmitting/receiving telescope with a diameter of 1.2m, uses a CW CO2 gas laser with an average emission power of kW, works at 10.6 μm, adopts a heterodyne detection mode, works at a distance of 1 000km, and has a tracking accuracy of 1 microradian (.
As early as the 1970s, Lincoln Lab demonstrated its ability to accurately track and acquire satellite Doppler images with a "fire pond". In 1976, the accuracy of measuring the spin of LAGEOS satellite at a distance of100 ~1200 km from the ground was 0. 1Hz. 1990, the improved "fire pond" has high power, wide bandwidth and the ability to identify ballistic missile warheads and decoys re-entering the atmosphere. 1In March, 990, Tang Huo obtained the Doppler images of the shooting range of suborbital probe rocket and inflatable reentry vehicle bait launched from 800 kilometers away. At the same time, the rocket is successfully and accurately tracked by incoherent argon ion lidar.
"Tang Huo" lidar successfully achieved long-distance high-precision tracking for the first time. However, its own equipment is not ideal, and there is still a considerable distance from the requirements of the Star Wars plan in terms of accuracy and reliability.
While the "Fire Pond" has stepped up its improvement and experiment, Hughes Aircraft Company has invested a huge sum of money to develop a giant experimental telescope device for the "Star Wars" project, which claims to be the most advanced laser beam control and aiming/tracking system in the world so far. Although its tactical indicators are unknown, it can be seen from the published photos that its volume is much larger than that of the "fire pond", which will undoubtedly make the development of large-scale precision measurement and tracking lidar take a new step.